Routing of vehicles requires digital map data. These map data may be available in a vector data format. Vector data in corresponding vector models describe space-related objects on the basis of points or nodes and also lines or edges. Vector data are therefore specified by means of coordinates and connections. These connections can reproduce the topology of an infrastructure network, particularly of a road network or traffic network. In this case, the vector data are conventionally enriched with relevant supplementary data or attribute data that are relevant to routing. Examples of such supplementary data are road names, road types, turn restrictions, signposts and a maximum speed permitted on a road. The vector data can be taken as a basis for computing a route for a vehicle, with position finding for the vehicle, for example by means of a GPS system, being able to be used to identify the current position of the vehicle. By comparing the currently recorded position of the vehicle and the computed route, it is possible to determine a deviation in the vehicle from the predefined route and to direct or steer the vehicle as appropriate directly or indirectly via the user. Meaningful navigation of a vehicle, particularly in a traffic network, requires relatively accurate data and a sufficient volume of supplementary or attribute data.
Besides navigation for individual vehicles, the digital map data can also be used for route planning for a vehicle fleet including many vehicles. In addition, the digital map data can also be used for directly controlling autonomously driving vehicles. Further, such digital map data can also be used for coordinating supporting measures in emergency areas.
Conventional methods for producing vector data that comprise digital map data involve the data being obtained from orthophotographs and updated. Orthophotographs are distortion-free true-to-scale depictions of the Earth's surface that are able to be derived from aerial or satellite images. The attribute or supplementary data required for the digital map data or the vector map are conventionally ascertained by traveling along the various possible routes, i.e. the attribute data are captured in situ by people involved in the project. Traveling along the routes usually involves video recordings being made by means of a camera, said video recordings being subsequently examined and manually evaluated in order to obtain the necessary attribute data or supplementary data. Therefore, capture of the supplementary or attribute data via the vector map is extremely laborious and time-consuming. Furthermore, manual evaluation of the video recordings or direct in-situ capture can easily involve errors or inaccuracies arising. One reason is the use of different cameras with different camera perspectives and inaccurate organization or association of the data on account of measurement at different times. In order to keep the map material up to date, regular inspections and corrections are required that in turn entail a high level of handling complexity.